1. Field of the Invention
The present invention relates generally to wheelchairs and scooters, and, more particularly, relates to a seat of a wheelchair or scooter, and, in greater particularity, relates to means for assisting the user to elevate oneself or to assist the user in removing oneself from the seat.
2. Description of the Prior Art
Wheelchairs are very important mobility vehicles for persons having a physical condition where mobility is otherwise limited by physical and/or mental impairment. Wheelchairs are present in great numbers in hospitals, nursing homes, rest homes, and at home. Further, there are many reasons to remove oneself from a seated position: to go to bed, to relieve oneself, to change clothes, to take a shower, for medical examinations, etc.
Wheelchairs come with many options that can greatly affect the price. Simple wheelchairs may cost several hundred dollars, and more fully accessorized wheelchairs may cost up to one thousand dollars. The addition of an electric drive and seat adjustable features to wheelchairs raise the cost to between 5 thousand to 10 thousand dollars. Another related product is called the electric scooter and an electric power chair. The cost of these varies greatly depending on features, but ranges from about 1 thousand to several thousand dollars. The electric scooter may be used outside and inside. The power chair is usually limited to the home.
Wheelchairs vary from simple to complex. A very simple wheelchair is called a transport chair and its main feature is that it is lightweight weighing only about 20 pounds. Rather than having two large wheels, a small wheel is placed on each corner of the frame. The seat is a fabric sling seat and secured to two horizontal seat rail tubes. Two widths are available typically. On more traditional wheelchairs, the end of each seat rail tube is mounted a plastic guide that slides up and down the vertical tubes which form an armrest on the top, that can not be removed. Two crossing pivoted tubes, one end attached to the seat rail tube and the other end to a lower frame tube allow the wheelchair to be folded. It has swing-away footrests. Such a wheelchair is sold by Drive Medical Design and Manufacturing.
A more upscale and traditional wheelchair has removable arm rests, a pair of large wheels in the rear and a pair of small wheels in the front, elevating leg rests, swingaway foot rests, fabric sling seat and back and is illustrated by Probasics Model EC10, for example. Additional features of other wheelchairs would include chrome plating; selection of seat widths, ranging from 18 inches to 26 inches; seat depth of 16 inches; a selection of weight capacity; full length armrests. Two pairs of crossed pivoted tubes support the seat rail tubes. In one wheelchair, the seat rail tube is further mounted to a single vertical sliding tube mounted inside a tube secured to the frame. One pair of crossed tubes is used between the sides. As the wheelchair is folded, the seat rail elevates and one end has a plastic guide that travels along a vertical tube where the seat back is secured.
Electric wheelchairs are significantly more expensive than regular wheelchairs and cost from several thousand up to almost 10 thousand dollars. These wheelchairs further add many additional features not available otherwise. Several example of such are sold by Invacare as Model Formula TRE, by Pride Mobility Products Corp. as the Jazzy 100, and by 21st. Century Scientific, Inc., as Model Bounder Plus H-Frame Power. For example, the Bounder comes with a chair seat that can recline, tilt, and elevate. All of these actions are provided by computer controlled electric motors driving crossed tubes under the chair seat. The Invacare model also provides recline, tilt and elevate of the chair seat in various combinations of movement. The elevate mode goes up to 7 inches. The seat fabric in these models are not of the sling design as is typical of the regular wheelchair, but have a cushion mounted in a rigid frame. No model is shown having the ability to just move the seat cushion.
For the user who does not require a wheelchair, but still lacks mobility, the electric scooter is an option. The electric scooter provides a cushioned seat mounted to a frame that includes the backrest. The seat may be adjustable in height, but not with a user on the seat. The seat is pivotally mounted to the seat frame for ease of mounting and dismounting. It further may have armrests that can be folded out of the way. Control of the scooter is through a tiller with handle bars with controls thereon. Typically, the scooter has three wheels with the back pair being driven. Such an electric scooter is sold by Pride Mobility Products Corp. as Model Go-Go Ultra.
In the standard wheelchairs and scooters, no provision is made for assisting the user in standing or being elevated. Several patents do disclose such means, but do not disclose seat controllable devices or any device that is portable from one wheelchair to another for such a purpose.
U.S. Pat. No. 3,985,389 discloses a mechanical/hydraulic elevating means attached to the frame for lifting the wheelchair vertically.
U.S. Pat. No. 4,613,151 discloses an electric wheelchair having the seat attached to four pivoting legs to lower the seat and to raise the seat to a standard position.
U.S. Pat. No. 4,949,408 discloses an electric wheelchair having a movable back and leg rest that allows the wheelchair to be converted to a horizontal bed for transferring the user to a bed.
U.S. Pat. No. 4,993,736 discloses wheelchair with a plurality of inflatable cushions under the seat for raising the seat and back to a higher position as a unit.
U.S. Pat. No. 5,108,202 discloses a wheelchair having a mechanical device for moving a sitting patient to a standing position.
U.S. Pat. No. 5,520,403 discloses a wheelchair having a complex mechanical device for elevating the seat within the wheelchair.
U.S. Pat. No. 5,513,867 discloses a wheelchair having a mechanical device for rotating the seat from the horizontal position to an almost vertical position wherein the user may stand.
U.S. Pat. No. 5,613,697 discloses a wheelchair having four hydraulic lifting devices for lifting the wheelchair to a higher position.
U.S. Pat. No. 6,431,650 discloses a wheelchair having a single hydraulic pump in the center of the seat frame and further having four tube-in-tube corners for allowing the seat to be raised vertically.
U.S. Pat. No. 7,040,641 discloses a user lifting device/hoist attached to the wheelchair, and further has a sliding seat to assist in standing the user.
U.S. Pat. No. 7,165,778 discloses a wheelchair having mechanical means to assist in the standing of a user by slanting and raising the seat.
These patents are incorporated by reference.
Accordingly, there is an established need for an improved mobility device having an optional seat having elevating and tilting features.